The 31-year-old will leave the BBC's One Show and the corporation itself after signing a three-year deal to front ITV's long-running breakfast show, according to the News of the World.
Bleakley, who can expect to host numerous other "primetime ITV entertainment shows" as well as GMTV, said: "[The One Show] has consumed my life in that time and I would not have had it any other way; I have made great friends and met some incredible people.
"I fully understand the BBC had to move more swiftly than I could, and as a result they've managed to help make my mind up for me."
She added that the BBC had been "nothing but supportive, fair and encouraging" during her time there, and that she is "eternally grateful for everything they have done".
Bleakley also paid tribute to former One Show co-host Adrian Chiles, who was previously confirmed to have also won an anchor role on the show, saying: "I am looking forward to a brand new experience at ITV, albeit with an old friend."
Bleakley had been offered a £900,000 pay rise by the BBC, but remained torn between staying at the corporation or moving to ITV to join Chiles, who left back in April.